Actuating mechanism for impact machines



June 16, 1953 E. c. LUNDEBERG 2,641,941

ACTUATING MECHANISM FOR IMPACT MACHINES Filed June 16. 1948 2Sheets-Sheet l E? fizz-82420?" gas a Lande5eqy Patented June 16, 1953UNITED STATES PATENT OFFICE ACTUATING MECHANISM FOR IMPACT MACHINES 8Claims.

1 The invention relates to an actuating mechanism for a machineforstriking sharp sudden blows against a piece. of work. The mechanismincludes a movable plunger adapted for carrying a suitable tool adaptedto act upon the work. This tool may be a riveting or upsetting tool, ora tool for marking part numbers and the like, or

' any other tool which can do its work with a sharp blow.

- One of the objects of the invention is to provide a mechanism of theclass described having means for adjusting the force of the blows struckby the tool. More specific objects of the invention are toprovide simpleand conveniently operable means for attaining the desired adjustment.

Other objects of the invention are to provide improved means for movingthe tool carrying plunger to quickly separate the tool from the workafter a blow has been struck, and to provide improved means for thenwithdrawing the tool carrying plunger and positioning it for the nextfollowing operation.

Still other objects of the invention will be apparent from the drawingsand from the following specification and claims.

In the drawings I have shown in detail a preferred embodiment of theinvention, but it will be understood that various changes may be madefrom the construction shown, and that the drawings are not to beconstrued as defining or limiting the scope of the invention, the claimsforming a part of this specification being relied upon for that purpose.

Of the drawings:

Fig. l is a longitudinal vertical sectional view of a machine having anactuating mechanism embodying the invention, this view being taken alongthe line l of Fig. 2.

Fig. 2 is a transverse vertical sectional view taken along the line '2-2of Fig. 1.

Fig. 3 is a horizontal sectional view taken along the line 3--3 ofFig. 1. r

, Fig. 4 is a horizontal sectional view taken along the line 4- l ofFig. l.-

Fig. 5 is a perspective View of the machine-o a reduced scale.

Referring to the drawing, H] is a main frame which is provided with ananvil 12. The anvil is adapted, as for instance by the provision of aT-slot M therein, for the holding of a fixture such as it suitable forholding a work piece such as W to be acted upon. The work piece whenengaged with the fixture is at or adjacent an impact position. Avertical plunger [3 is provided above the anvil I2, this plunger beingmovable toward and away from the anvil and the said impact position. Theplunger I8 is adapted at its lower end for forcing a tool such asagainst a work piece on the fixture and adjacent the impact position.The tool 20 may be carried directly by the plunger I8 and it is formedor constructed for suitably acting upon the work piece.

It will be understood that the term vertical, as applied to the plunger[8 and as applied to various other parts, is herein used only in arelative sense and for purposes of simplicity of description. The saidterm is not to be interpreted as used in a restrictive sense, and theseveral parts may be positioned otherwise than vertically so long as thedescribed relationship between them is maintained.

Preferably the plunger I8 is partly within a suitable housing 22 carriedby or formed as a part of the frame It. As shown the housing 22 isstructurally separate from the frame In, the frame l0 having a verticaldovetail opening which receives and fits a portion of the housing asclearly shown in Figs. 3 and 4. The housing 22 is preferably verticallyadjustable with respect to the frame Ill and as shown the housingcarries a bracket 24 at the rear having a vertical aperture therein. Astud 26 projects upward from the frame It through the said aperture inthe bracket 24. Nuts 28, 28 on the stud 26 engage the bracket 24 and itwill be seen that by adjusting the said nuts 28, 28 the housing can bevertically adjusted with respect to the frame. Preferably, one or moreset screws 30, 30 are provided for locking the housing in its verticallyadjusted position.

A second vertical plunger 32 is provided which is above the plunger 18and is in alignment therewith. This plunger is also vertically movabletoward and away from the anvil l2 or the impact position. The lower partof the plunger 32 is er 32 is connected with the said piston 36. By

means of pipes 38 and air may be admitted to the cylinder 33 above thepiston 36 to move the piston and the plunger downwardly and air may beadmitted below the piston to move the piston and the plunger 32upwardly. The pipes 38 and 40 are connected with a suitable valvemechanism not shown, this valve mechanism serving to connect either thepipe 38 or the pipe 44 with a source of air under pressure. The valvemechanism may be operated manually or by means of a suitableelectromagnetic operating mechanism.

A releasable latch 42 is provided for holding the first plunger 48 inits uppermost position as shown in Fig. 1. The details of this latch maybe varied but preferably and as shown the latch is located within thehousing 22 and is in the form of a substantially vertical bar. The baror latch 42 is pivoted near its upper end to the top wall of the housing22 for movement about a fixed axis. As shown, the upper end of the latch42 projects into an opening in the top wall of the housing and is heldby a horizontal pivot pin 44. The latch 42 is provided near its lowerend with a transversely movable tooth 45 which is positioned and shapedto engage with a lug 48 secured to a collar 50 connected with the upperpart of the plunger l8. Whenthe tooth 46 is engaged with the lug 48 theplunger is held in its uppermost position as shown in Fig. 2. A spring52 engages the latch and also engages the side wall of the housing 22and serves to bias the latch into its engaging position as shown.

A heavy spring is connected with and interposed between the two plungersl and 32 which spring is compressed upon movement of the second plungertoward the anvil or impact position while the first plunger is held bythe latch 42. Preferably the said heavy spring is a coil compressionspring 54 which engages at its lower end with the said collar 56 on theplunger I8 and whichv engages at its upper end with a collar 55 at thelower end of the plunger 32. The spring 54 is compressed upon movementof the plunger 32 while the plunger I8 is held by the latch 42.

An element 58 is provided which is engageable by a flange '50 on thecollar 55, and which is moved transversely when so engaged. The saidelement 58 is so positioned that it is engaged by the flange 50 onlyafter the plunger 32 has moved to a substantial extent so as to compressthe heavy spring 54. When the said element 58 is engaged as described itserves to move the latch 42 transversely so as to disengage the tooth 48thereof from the lug 48 on the plunger IS, the said plunger being thusreleased so that the spring 54 can drive it toward the anvil or impactposition independently of the second plunger 32. When the plunger [8 isdriven downwardly as described the tool is forced against a work piece Wheld by the fixture l6.

When the tool 20 is directly carried by the plunger IE it strikes a hardblow against the work piece.

Preferably and in accordance with one phase of the present invention,the latch moving element 58 is longitudinally or vertically adjustableso as to be engaged by the flange 60 after movements of the plunger 32to varying extents. When the latch 42 is a substantially vertical bar asshown, the element 58 is vertically adjustable along the bar. When theelement 58 is in a relatively elevated position it moves the latch 42 torelease the plunger [8 after only a small downward movement of theplunger 32 and after the spring 54 has been compressed to only arelatively small extent. With the spring 54 only slightly compressed itexerts a relatively small force on the plunger I8 and the plunger ismoved to cause the tool 2!! thereon to strike only a light blow againstthe work piece. As the element 53 is adjusted in the downward directionthe plunger 32 moves to successively greater extents and the spring 54is compressed to successively greater extents before the said element 58acts to move the latch and release the plunger l8. Thus the forceexerted upon the plunger l8 by the spring 54 is successively increasedasthe element 58 is adjusted downward and the tool 20 strikesincreasingly sharper blows upon the Work piece. By adjusting the element58 downwardly or upwardly the force of the blows struck by the tool 20can be varied to any de-- sired extent within a predetermined range.

A suitable manually operable mechanism is preferably provided foreffecting the described vertical adjustment of the element 58. As shown,the element 58 is apertured to receive the latch and is guided formovement therealong. The said element is pivotally connected at '5! withthe lower end portion of a substantially vertical rod 62 which isclosely adjacent the latch 42. The upper end portion of the rod =62 isthreaded and projects through an opening in the top wall of the housing22. A coil spring 53 surrounds the rod 52, this spring abutting at itslower end against the element 53 and abutting at its upper end againstthe top wall of the housing, the spring thus serving to bias the element58 for downward movement. A knurled nut 64 has threaded engagement withthe upper end portion of the rod 62, the said nut resting upon the topwall of the housing 22. The opening in the top wall of the housing 22 islarger than the rod 62, thus permitting the rod to rock slightly as itslower end is moved by the element 58.

It will be seen that the nut 64 is conveniently positioned at the frontof the machine and that the operator, by turning the nut, can raise orlower the latch moving element 58. When the nut 54 is turned in onedirection the element 58 is moved upward in opposition to the spring 63.When the nut 64 is turned in the opposite direction the element 58 ismoved downward by the spring '53. As shown, the rod 52 is flattened atone side as indicated at 65 and this flattened portion carriesvertically spaced numerals which serve to indicate the extent ofadjustment of the element 58.

Preferably a relatively light spring is provided which is connected withthe plunger IB and which is tensioned upon the independent downwardmovement of the said plunger by the heavy spring 54. The relativelylight spring serves, immediately after movement of the plunger to themaximum extent toward the impact position, to move the plunger I8 awayfrom the said impact position. When the tool 20 is carried directly bythe plunger It, the said light spring serves to move the tool out ofengagement with the work piece. The said light spring may be variouslyformed and connected, but preferably and as shown a coil spring 63 isprovided which is within a central aperture in the plunger It. Thespring '88 surrounds a vertical rod 75 which is vertically movable withrespect to the plunger [8 and which extends upward through the coilspring 54, being rigidly connected at its upper end with the plunger 32or with the collar 56 thereon. The rod in has a head at its lower endand the spring 68 abuts at its lower end against the said head on therod 75 and abuts at its upper end against a shoulder. formed withspring54.

in the plunger It. It will be seen that, by reason of the describedconnection, the said spring 68 serves to bias. the plunger l8 for upwardmovement relatively to the plunger 3'2.

It will be seen that the rod 10 serves, ordinarily in conjunction with aspring such 'as '68,

movement being cushioned by the spring '68 and being continued until theplunger I8 is again engaged and held by the latch 42. Thus the partsarerestored to their initial positions and are ready for a subsequentcycle of operations.

In operation, after a work piece such as W has been put in place on thefixture IS, the air valve is manipulated to admit air to the top of thecylinder 34, thus forcing the piston 36 and the plunger 32 downward andcompressing the When the flange 60 engages the element 5!! the latch 42is, disengaged from the plunger l8 which is then driven downwardly bythe'spring so as to cause the tool to strike a sharp blow against thework piece. The spring 68 immediately withdraws the plunger l8 and thetool 29 from the work piece and the valve mechanism is reversed to admitair to the bottom of the cylinder 34, thus raising the plunger 32.. Asthe plunger 32 moves upwardly it serves, by means ,of the rod E0 and thespring 68, to elevate the v plunger l8 to its initial position where itis again engaged by the latch 42. W can be removed and a new one put inplace,

after which the beforedescribed. cycle of operations is repeated. Theforce of the blow exerted by the tool 20 can be adjusted by means of thenut 64 as already described.

What I claim is:

1. In an actuating mechanism for an impact machine, the combination of aframe, a plunger movable longitudinally relatively to said frame towardan impact position, a latch, means for mounting the latch on said frame,said mountin means being constructed to permit transverse movement ofthe latch but to prevent longitudinal movement thereof, means biasingsaid latch for engagement with the plunger to hold it in a positionremote from the said impact position, a second plunger in alignment withthe first plunger and movable lon itudinally relatively to the frame,means connected with the second plunger for moving it toward the saidimpact position, a heavy spring connected with and interposed betweenthe two plungerswhich spring is tensioned upon movement of the secondplunger .toward the said impact position while the first in adjustedposition, being engaged and displaced upon movement of the said plungertoward the impact position, said element being connected to said latchin any position thereof to utilize the displacement of the said elementfor moving the latch transversely so as to release the first plunger andthus permit the heavy spring to drive the first plunger toward the saidimpact position independently of the second plunger, and means Then thework piece 6 for longitudinally adjusting the latch moving element tochange the position .at which the said elementis engaged by the secondplunger and to thus change the amount of spring tension prior to therelease of the first plunger with a resultant change in the amount offorce exerted by the spring to move the said first plunger toward thesaid impact position.

2. In an actuating mechanism for an impact machine, the combination of ahousing, a plunger partly within the housing and projecting therefromdownwardly toward an impact position, the said plunger being verticallymovable downwardly relatively to the housing and toward the said impactposition, a latch located within the housing, means within the housingfor mounting the latchthereon, the said mounting means being constructedto permit transverse movement of the latch but to prevent longitudinalmovement thereof, means biasing said latch for engagement with theplunger to hold it in its uppermost position, a second plunger partlywithin the housing in alignment with the first plunger and verticallymovable relatively to the housing, means connected with the secondplunger for moving it downwardly, a heavy spring connected with andinterposed between the two plungers which spring is tensioned upondownward movement of the second plunger while the first plunger is heldby the latch, a latch moving element within the housing mounted forlongitudinal adjustment along the path of movement of said secondplunger and, in adjusted position, being engaged and displaced upondownward movement of the said plunger, said element being connected tosaid latch in any position thereof to utilize the displacement of thesaid element for moving thev latch transversely so as to release thefirst plunger and thus to permit the heavy spring to drive the firstplunger downwardly toward the said impact position independently of thesecond plunger, and manually operable means accessible at the exteriorof the housing and connected with the latch moving element forvertically adjusting the said element with respect to the latch so as tochange the position at which the element is engaged by the secondplunger and to thus change the amount of spring compression prior to therelease of the first plunger with a resultant change in the amount offorce acting to move the said first plunger and a, tool carried therebydownwardly toward the said impact position.

3, In an actuating mechanism for an impact machine, the combination of aframe, a plunger movablevertically downwardly relatively to said frametoward an impact position, a substantially vertical latch having a toothnear its lower end, means for connecting the latch with the frame formovement about a fixed horizontal axis near the upper end of the latch,means for biasing the latch for movement about the said axis totransversely move the said tooth into engage ment with the plunger tohold 'it in its uppermost position, a second plunger above the firstplunger and vertically movable relatively to the frame, means connectedwith the second plunger for moving it downwardly, a heavy springconnected with and interposed between the two plungers which spring istensioned upon down" ward movement of the second plunger while the firstplunger is held by the latch, a latch moving element mounted forvertical adjustment along in adjusted position, being engaged and dis-16.

placed upon downward movement of the said plunger, said element beingconnected to said latch in any position thereof to utilize thedisplacement of the said element for pivotally mov ing the latch inopposition to its bias so as to release the first plunger and to thuspermit the heavy spring to drive the first plunger downwardlyindependently of the second plunger, and means for vertically adjustingthe said latch moving element with respect to the latch to change theposition at which the said element is engaged by the second plunger andto thus change the amount of spring tension prior to the release of thefirst plunger with a resultant change in the amount of force exerted bythe spring to move the said first plunger downwardly toward the saidimpact position.

4. In an actuating mechanism for an impact machine, the combination of aframe, a plunger movable vertically downwardly relatively to said frametoward an impact position, a substantially vertical latch having a toothnear its lower end, means for connecting the latch with the frame formovement about a fixed horizontal axis near the upper end of the latch,means for biasing the latch for movement about e said axis totransversely move the said tooth into engagement with the plunger, asecond plunger above the first plunger and vertically movable relativelyto the frame, means connected with the second plunger for moving itdownwardly, a heavy compression spring connected with and interposedbetween the two plungers which, spring is compressed upon downwardmovement of the second plunger while the first plunger is held by thelatch, a substantially vertical rod adjacent the latch and mounted forvertical adjustment relatively thereto, a latch moving element carriedby the rod and vertically adjustable therewith along the path ofmovement of the second plunger and, in adjusted position, being engagedand displaced upon downward movement of the said plunger, said elementbeing connected to said latch in any position thereof to utilize thedisplacement of the said element for pivotally moving the latch inopposition to its bias so as to release the first plunger and to thuspermit the heavy spring to drive the first plunger downwardlyindependently of the second plunger, and means for vertically adjustingthe said rod and the said latch moving element to change the position atwhich the said element is engaged by the second plunger and to thuschange the amount of spring compression prior to the release of thefirst plunger with a resultant change in the amount of force exerted bythe spring to move the said first plunger downwardly toward the saidimpact position. 7

5. in an actuating mechanism for an impact machine, the combination of aframe, a plunger movable vertically downwardly relatively to said frametoward an impact position, a substantially vertical latch having a toothnear its lower end, means for connecting the latch with the frame formovement about a fixed horizontal axis near the upper end of the latch,means for biasing the latch for movement about the said axis totransversely move the said tooth into engagement with the plunger tohold it in its uppermost position, a second. plunger above the firstplunger and vertically movable relatively to the frame, means connectedwith the second plunger for moving it downwardly, a heavy compressionspring connected with and interposed between the two plungers whichspring is compressed upon downward movement of the. second plunger whilethe first plunger is held by the latch, a substantially vertical rodadjacent the latch, the said rod being vertically-movable and beingthreaded at its upper end, a spring for biasing the rod downwardly, anut engaging the threaded portion of the rod and serving upon rotationto cause the rod to move downwardly or upwardly, the said rod beingmoved downwardly by the spring and being moved upwardly by the nut, anda latch movingelement carried by the said rod near the lower end thereofand vertically movable therewith along the path of movement of thesecond plunger and, in adjusted position, being engaged and displacedupon downward movement of the said plunger, said element being connectedto said latch in any position thereof to utilize the displacement of thesaid element for .pivotally moving the latch in opposition to its biasso as to release the first plunger and to thus permit the heavy springto drive the first plunger downwardly independently of the secondplunger, the vertical movement of the said element by means of the rodserving to change the position at which the element is engaged by thesecond plunger and to thus change the amount of compression of the heavyspring prior to the release of the first plunger with a resultant changein the amount of force exerted by the spring to move the said firstplunger downwardly toward the said impact position.

6. In an. actuating mechanism for an impact machine, the combination ofa frame, a plunger longitudinally movable relatively to said frametoward an impact position, a latch, means for mounting the latch on saidframe, said mounting means being constructed to permit transversemovement of the latch but to prevent longitudinal movement thereof,means biasing said latch for engagement with the plunger to hold it in aposition remote from the said impact position, a second plunger inalignment with the first plunger and longitudinally movable relativelyto the frame, means connected with the second plunger for moving ittoward the impact position, a heavy spring connected with and interposedbetween the two plungers which spring is tensioned upon movement of thesecond plunger toward the impact position while the said first plungeris held by the latch, a latch moving element positioned in the path ofmovement of the second plunger and being engaged and displaced uponmovement of the said plunger toward the impact position, the saidelement being connected to the latch to utilize the displacement of thesaid element for IIlOVlIlg the latch to release the first plunger and tothus permit the heavy spring .to drive the said first plunger toward thesaid impact position independently of the second plunger, a light springconnected with the first plunger for moving it away from the said impactposition independently of the second plunger, and means for tensioningthe last said spring upon independent movement of the first plunger bythe said heavy spring, the said light spring upon movement of the firstplunger to the maximum extent toward the said impact position serving toimmediately thereafter move the said plunger in the direction away fromthe said position.

'7. In an actuating mechanism for an impact machine, the combination ofa frame, a plunger longitudinally movable relatively to the frame towardand away from an impact position, a latch, means for mounting the latchon said frame, said mounting means being constructed to permittransverse movement of thelatch but to prevent longitudinal movementthereof, means biasing said latch for engagement with the plunger tohold it in a position remote from the impact position, a second plungerin alignment with the first plunger and longitudinally movablerelatively to the frame, means connected with the second plunger formoving it successively toward and away from the impact position, a heavyspring connected with and interposed between the two plungers whichspring is tensioned upon movement of the second plunger toward theimpact position while the said first plunger is held by the latch, alatch moving element positioned in the path of movement of the secondplunger and being engaged and displaced upon movement of the saidplunger toward the impact position, the said element being connected tothe latch to utilize the displacement of the said element for moving thelatch to release the first plunger and to thus permit the heavy springto drive the first plunger toward the impact position independently ofthe second plunger, and a lost motion connection between the firstplunger and thesecond plunger which connection includes a light springbiasing the first plunger toward the second plunger, the

light spring of the said connection being tensioned upon independentmovement of the first plunger by the heavy spring and the saidconnection upon subsequent movement of the second plunger in thedirection away from the impact position serving to move the firstplunger away from the impact position to a position at which it isreengaged by the latch. I

I 8. In an actuating mechanism for an impact machine, the combination ofa frame, a plunger longitudinally movable relatively. to the frametoward and away from an impact position and adapted to force a toolagainst a work piece adjacent the said impact position, a, latch, meansfor mounting the latch on said frame, said mounting means beingconstructed to permit transverse movement of the latch but to preventlongitudinal movement thereof, means biasing said latch for engagementwith the plunger to hold it in a position remote from the impactposition, a second plunger in alignment with the first plunger andlongitudinally movable relatively to the frame, means connected with thesecond plunger for moving it successively toward and away from theimpact position, a heavy compression coil spring connected with andinterposed between the two plungers which spring is compressed uponmovement of the second plunger toward the impact position while the saidfirst plunger is held by the latch, a latch moving element positioned inthe path of movement of the second plunger and being engaged anddisplaced upon movement of the said plunger toward the impact position,the said element being connected to the latch to utilize thedisplacement of the said element for moving the latch to release thefirst plunger and. to thus permit the heavy spring to drive the firstplunger toward the impact position independently of the second plunger,a rod connected with the first plunger and extending through the saidcoil spring and into an aperture in the second plunger, and a light coilspring surrounding the rod and engaging the first plunger to bias ittoward the second plunger, the said light spring being compressed uponindependent movement of the first plunger by the heavy spring and thesaid light spring upon References Cited in the file of this patentUNITED STATES PATENTS Number Name Date 2,319,796 Cooper May 25, 1943Kovach Sept. 16, 1947

